#!/usr/bin/env python
# -*- coding:utf-8 -*-
__author__ = 'wshu'
__version__ = '1.0'
"""
    ***********************************
    *  @filename : downloadmiddleware.py
    *  @Author : wshu
    *  @CodeDate : 2020/3/26 15:50
    *  @Software : PyCharm
    ***********************************
    爬虫系统下载中间件扩展模块
"""
from scrapy import signals
from utils.UserAgentList import get_user_agent

class HfbotV1SpiderMiddleware(object):
    # Not all methods need to be defined. If a method is not defined,
    # scrapy acts as if the spider middleware does not modify the
    # passed objects.

    @classmethod
    def from_crawler(cls, crawler):
        # This method is used by Scrapy to create your spiders.
        s = cls()
        crawler.signals.connect(s.spider_opened, signal=signals.spider_opened)
        return s

    def process_spider_input(self, response, spider):
        # Called for each response that goes through the spider
        # middleware and into the spider.

        # Should return None or raise an exception.
        return None

    def process_spider_output(self, response, result, spider):
        # Called with the results returned from the Spider, after
        # it has processed the response.

        # Must return an iterable of Request, dict or Item objects.
        for i in result:
            yield i

    def process_spider_exception(self, response, exception, spider):
        # Called when a spider or process_spider_input() method
        # (from other spider middleware) raises an exception.

        # Should return either None or an iterable of Request, dict
        # or Item objects.
        pass

    def process_start_requests(self, start_requests, spider):
        # Called with the start requests of the spider, and works
        # similarly to the process_spider_output() method, except
        # that it doesn’t have a response associated.

        # Must return only requests (not items).
        for r in start_requests:
            yield r

    def spider_opened(self, spider):
        spider.logger.info('Spider opened: %s' % spider.name)


class HfbotV1DownloaderMiddleware(object):
    # Not all methods need to be defined. If a method is not defined,
    # scrapy acts as if the downloader middleware does not modify the
    # passed objects.

    @classmethod
    def from_crawler(cls, crawler):
        # This method is used by Scrapy to create your spiders.
        s = cls()
        crawler.signals.connect(s.spider_opened, signal=signals.spider_opened)
        return s

    def process_request(self, request, spider):
        # Called for each request that goes through the downloader
        # middleware.

        # Must either:
        # - return None: continue processing this request
        # - or return a Response object
        # - or return a Request object
        # - or raise IgnoreRequest: process_exception() methods of
        #   installed downloader middleware will be called
        return None

    def process_response(self, request, response, spider):
        # Called with the response returned from the downloader.

        # Must either;
        # - return a Response object
        # - return a Request object
        # - or raise IgnoreRequest
        return response

    def process_exception(self, request, exception, spider):
        # Called when a download handler or a process_request()
        # (from other downloader middleware) raises an exception.

        # Must either:
        # - return None: continue processing this exception
        # - return a Response object: stops process_exception() chain
        # - return a Request object: stops process_exception() chain
        pass

    def spider_opened(self, spider):
        spider.logger.info('Spider opened: %s' % spider.name)

class HfProxyMiddleware(object):
    """
    代理配置
    """
    def process_request(self, request, spider):
        request.meta['porxy'] = 'http://10.101.1.190:3129'


class HfHeaderMiddleware(object):
    """
    UserAgent 配置
    """
    def __init__(self):
        self.user_agent = get_user_agent()

    def process_request(self, request, spider):
        request.headers.setdefault('User-Agent', self.user_agent)
        request.headers.setdefault('Referer', 'https://www.cec.com.cn/')

class HeaderMiddleware(object):
    """
    Header协议配置
    """
    def __init__(self):
        self.user_agent = get_user_agent()

    def process_request(self, request, spider):
        headers_list = {
            'Accept': 'text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8',
            'Accept-Language': 'zh-CN,zh;q=0.8,en;q=0.6,zh-TW;q=0.4,und;q=0.2',
            'Cache-Control': 'no-cache',
            'Connection': 'keep-alive',
            'Accept-Encoding': 'gzip, deflate, sdch',
            'Transfer-Encoding': 'chunked',
            'Referer': 'https://www.cec.com.cn/',
            'User-Agent': self.user_agent
        }
        for k, v in headers_list.items():
            request.headers.setdefault(k, v)